Sorry for the low rating- I can see you've done everything you could to make it look good, but it just hasn't worked.

The wall texture makes me want to puke really, change it to something less reflective and more in the style of something normal, i.e. you have used a dust flooring, use a dust wall texture.

The cover boxes are all facing the same direction- rotate a couple of them to make it look better.

Maybe you could add a large light at the bottom (which is a chance to do something fancy with some brushwork).

Also even out the top middle bit, because its not symmetrical at the moment.

You need to clip the ladder textures as well.

There is a lot to improve upon, but I think if you redo it, it could be a successful map.

Also if you have time, add a 3D skybox.